AB1613 MEFV GENE TEST – WHO’S ORDERING THEM AND WHY?
Authors: S. Shan, M. Mian
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Familial Mediterranean Fever (FMF) is a rare autosomal recessive illness of periodic fever syndrome that primarily affects the Mediterranean population [1]. No single specific diagnostic test exists to accurately diagnose FMF. Testing of the MEFV gene is the primary investigation of choice to support a diagnosis of FMF [2]. Little is known regarding MEFV testing within Australian cohorts. <h3>Objectives</h3> We aim to describe the pattern of ordering for FMF genetic testing via the ordering of MEFV gene, and the clinical circumstances surrounding its request in a large Australian referral centre. <h3>Methods</h3> We retrospectively identified all MEFV genetic testing ordered within a large public referral centre over a five-year period. We collected information regarding the clinical scenario indicating genetic testing, presenting symptoms and adherence to Tel HaShomer diagnostic criteria as well as whether the genetic testing impacted the final diagnosis. <h3>Results</h3> 64 MEFV genetic testing were ordered through the five-year period, seven were within the paediatric population. The median age of the cohort was 37, 56.3% were male sex. There is a median of five flares of FMF prior to MEFV testing with median time from last flare being two months. 53.1% of the tests were ordered in an inpatient setting, rest were through outpatient. Rheumatology ordered the most MEFV genetic testing in 67.2% of the cohort, followed by Infectious Diseases in 10.9% and General Medicine in 7.8% of the cohort. 79.7% of the participants satisfied the Tel HaShomer criteria for clinical diagnosis of FMF prior to genetic testing. MEFV genetic testing provided a positive diagnostic result in 21.9% (14 participants), there were seven homozygotes, seven compound heterozygotes and eight heterozygotes. Only one of the 14 participants with a positive MEFV test did not satisfy the clinical diagnostic criteria. A total of 36 mutated alleles were identified and M694V was the most frequent mutation appearing in 47.2% of the mutations identified. Peritonitis was the most common presentation in 67.2% of the cohort. One participant had amyloidosis as their presentation. 43.8% of the cohort was commenced on colchicine prior to genetic testing. <h3>Conclusion</h3> MEFV testing is most commonly ordered by Rheumatology than other specialities. While the genetic testing can be useful in a diagnostic dilemma, it also adds further diagnostic certainty if positive in those who satisfy the clinical diagnostic criteria. <h3>References</h3> [1] Sonmez HE, Batu ED, Ozen S. Familial Mediterranean fever: current perspectives. J Inflamm Res. 2016;9:13-20. [2] Mehmet E. TEZCAN MA, Ridvan MERCAN, Mehmet ALIUSTAOGLU, SARGIN2 M. MEFV gene testing may guide physicians for early diagnosis of familial Mediterranean fever. MEFV gene testing may guide physicians for early diagnosis of familial Mediterranean fever International Journal of Rheumatic Diseases. 2018;21(7):1452-7. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.